FTSE 250 trade show organiser UBM has begun the hunt for a new chairman after the veteran US investment banker John Botts told fellow directors he was planning to retire.

The company, which also publishes titles including Farmers Guardian and owns the press release distributor PR Newswire, is thought to have appointed headhunters to find a successor.

Mr Botts, who turns 71 next month, has been chairman since 2007, having joined the board a decade earlier. He could leave as soon as the annual shareholders' meeting in May, depending on the speed of the search.

Under the chief executive, David Levin, UBM has reduced its exposure to print and expanded to run more digital services and events such as a series of jewellery fairs in China. It has a market value of £1.1bn and operating profit was flat last year at £172m.

Mr Levin and Mr Botts worked together at Euromoney, the business publisher, where Mr Botts still sits on the board.